Griffin Silver Sword is a Diagram in the Witcher 3: Wild Hunt that can be crafted by a Blacksmith (Weapons) or Armorsmith (Armor).
- 180 Damage
- Bonus experience from Monsters +20%
- Sign Intensity +5%
- Go to Heatherton and head north there is a small tower off the coast with the draw bridge up. once you get there a level 14 wyvern will attack you. As long as Roach is in the area with you it will focus on him allowing you to easily dispatch it. when it starts flying you can knock it down with Aard or a crossbow bolt. once it is killed walk to the bridge area and look down you should see a place of power below you. make your way down to it, there is a underwater cave nearby. in the water there are six drowners three outside of the entrance and three inside. Kill them with your Crossbow underwater and proceed inside once you get to the area with the bridge drawn there is a ladder near the door you entered through. go up it and the diagram will be in this room.